the quadrajet in my trans am is in serious need of a rebuild. Its one of the comp. controlled ones so im not ganna try to rebuild it myself. the guy at autozone said that i should get a holly instead because quadrajets are crap and the holly is cheaper anyway. i was wondering if this is a logical thing to do considering i have one i can get for free. I figured that if i unplugged all the computer **** then an engine light would come on, or the distributor would freak out. He said he did it to his camaro with no problems and it ran better without tha quad anyway.

does this make anysense? what do i have to do so that it will run normal? and what is the advantage/disadvantage of a holly vs. quadrajet?

 

I know a lot of people that have actually switched from a holley to a quadrajet. They made the switch because the quad is not as temperamental as the holley and easier to tune. However these aren't computer controlled.

Free Holley! I would take it. It probably flows more than what you have now. If the distributor is computer controlled, it won't work with computer disabled. You would need to get an HEI.

 

The parts guy is full of crap. The Holley isn't cheaper. Another case of telling you what you want to hear so he can make a sale. You can run a non-CC carb with a CC distributor, but you're going to sacrifice something - most likely fuel economy. It can, however, be done properly with a non-CC distributor.

Let's go through the whole sequence:

Holley carb - what exactly do you have available for "free"? Most likely it will need a rebuild. It probably doesn't have electric choke. And, the biggest downer, it probably isn't the right one for your engine. Even if none of those things is true, you have a TH700-R4 transmission, which requires special TV cable geometry, which you'll have to address (or burn out your tranny). And, the Holley, unless it is a 4165 or 4175 model, won't bolt to your intake manifold, which means you'll have to get an adapter for it, which raises the carb - the proper thing to do is to get an intake manifold which will accomodate the square bore carb. You'll also need some cable brackets, and the aforementioned non-CC distributor. Don't forget, your air cleaner won't fit.

So, going to a proper Holley will cost something like this:
Carb - at least $300, probably more.
Intake manifold - $140
Distributor (Summit HEI) - $140 (the "good" one is $160)
Air cleaner - $20
Gaskets, brackets, fuel line, misc. - $50-$100
Plus the hassle of getting it all changed, cable geometry correct, and getting it tuned. It could be argued that the job could be done with used or JY parts, but then you'd have the hassles and unknowns of using used or JY parts.

Or:
Rebuilt CC q-jet - $375

 

or of course rebuild the cc-qjet yourself, $40 for the kit, maybe another $100 (absolute max), to purchase specialty tools and other parts that may be worn out and not in the rebuild kit (float, choke pulloff, etc.)

Or go non-cc q-jet and non-cc dist. just to throw in another option.

 

ok, just a bystander on the comversation but is the tranney on the '86 '87 ish cc quadraJUNK also computer controlled as far as overdrive and shift patterns and possibly torque converter lockup?

 

Yeah, what five7 said but don't forget about the torque converter lock up which the ecm won't control without the tps sensor. Also rebuilding the q-jet is easier than most think.

Besides, what kind of gains will a holley give you on top of a 305? other than worse mileage?

 

Hi Guys (New Member Here)

I am from the UK

I have done a Holley conversion on my 1987 Camaro Z28.... and it was worth every penny (cent) .... but you will have to change a few things to make it work.

firstly you will need a 600cfm or 600 double pumper or even a 750cfm Holley Carb, then you will have to get a Edelbrock performer manifold (pick up a heat displacement plate while you are there), a Mallory Marine Vac Advance Distributor and finally a low slung air filter to clear the hood.

by doing this you will bypass the computer and take tha engine back to basics.... no sensors or any other computerised rubbish to give you problems.. just plane old mechanical muscle.

dont let the choke worry you if you really want one, put a manual one on, the carbs i mentioned can be supplied with either, and it is cheaper for a manual. if not (like i have) lock the choke in position and let her warm up for a min.

while you have the manifold off you might think about changing the cam shaft to a street strip one.

Oh yes! as for the check engine light...take the bulb out.. you don't need it anymore

p.s mpg on a 600 double pumper around town is 25mpg and 28 on a run
on my friends 600cfm 28 and 32 respectively
mine has been done for just over a year and the performance is far better than the Quadrajet

 

how would you go about the tv cable? five7kid?